1. Field
One or more embodiments of the present invention relate to a method, medium, and apparatus encoding and/or decoding an image, and more particularly, to a method, medium, and apparatus encoding and/or decoding an image by considering human psycho-visual characteristics.
2. Description of the Related Art
In audio coding, an example psycho-acoustic model based on a human acoustic characteristic may be applied during an encoding operation to set a masking threshold such that a different number of bits are assigned to each frequency region.
Similarly, there are image coding technologies that are based on human psycho-visual characteristic. Examples of such coding technologies include using a particular format weighting of luminance and chrominance information, such as a YUV format, and using a quantization matrix in a discrete cosine transform (DCT) applied to the information to separate and code the information according frequency components. In these examples, the YUV format may compress data by assigning less bits to chrominance information than luminance information based on the characteristic that human eyesight is not as sensitive to changes in chromaticity. DCT divides the information into frequency ranges, e.g., a low frequency range and a high frequency range, and reduces the number of bits assigned to quantizing the high frequency regions compared to quantizing the low frequency regions based on the human psycho-visual characteristic of human eyesight's increased insensitivity to high frequency ranges.